If you want to enjoy the full features of Windows 10, you need to activate it with a serial key. A serial key is a 25-character code that verifies that your copy of Windows is genuine and not used on more devices than the Microsoft Software License Terms allow. In this article, we will show you how to find your serial key and how to use it to activate Windows 10.
Where to Find Your Serial Key
Depending on how you got your copy of Windows 10, you may have a serial key printed on a sticker, stored in an email, or linked to your Microsoft account. Here are some common ways to find your serial key:
If you bought a new PC that came with Windows 10 preinstalled, the serial key should be on a Certificate of Authenticity (COA) sticker on the device.
If you bought a physical copy of Windows 10 from a retailer, the serial key should be on a card inside the box.
If you bought a digital copy of Windows 10 from the Microsoft Store or another online store, the serial key should be in the confirmation email that you received after the purchase.
If you upgraded to Windows 10 for free from an eligible device running a genuine copy of Windows 7 or Windows 8.1, you don't need a serial key. You have a digital license that is automatically linked to your Microsoft account. You can use the Activation troubleshooter in the Get Help app to check your activation status and link your account if needed.
How to Use Your Serial Key to Activate Windows 10
Once you have your serial key, you can use it to activate Windows 10 on your device. Here are the steps to follow:
Go to Settings > Update & Security > Activation.
If you see a message that says \"Windows is not activated\", click Change product key.
Enter your serial key and click Next.
Follow the on-screen instructions to complete the activation process.
If you see a message that says \"Windows is activated with a digital license\", you don't need to enter a serial key. Your device is already activated and linked to your Microsoft account.
Troubleshooting Activation Issues
Sometimes, you may encounter some issues when trying to activate Windows 10 with a serial key. For example, you may see an error message that says \"This product key didn't work\" or \"The product key you entered didn't work\". Here are some possible reasons and solutions for these issues:
You entered an incorrect or invalid serial key. Make sure that you typed the serial key exactly as it appears on the sticker, card, or email. Check for typos and case sensitivity.
You used a serial key that has already been used on another device. You can only use a serial key on one device at a time. If you want to activate Windows 10 on another device, you need to buy a new serial key or use a different activation method.
You used a serial key that is not compatible with your edition or version of Windows 10. For example, you can't use a Windows 10 Home serial key to activate Windows 10 Pro, or a Windows 10 version 1909 serial key to activate Windows 10 version 2004. Make sure that your serial key matches your edition and version of Windows 10.
You made a significant hardware change on your device, such as replacing the motherboard or hard drive. This may affect your activation status and require you to reactivate Windows 10. If you have a digital license linked to your Microsoft account, you can use the Activation troubleshooter in the Get Help app to reactivate Windows 10. If you have a serial key, you may need to enter it again or contact Microsoft support for assistance.
If none of these solutions work for you, you can contact Microsoft support for more help. You can also visit the Microsoft support website for more information on how to activate Windows 10 with a serial key. aa16f39245